With the full version of XMind: ZEN, you can have your mind maps exported or printed without a watermark, please purchase a subscription for XMind: ZEN here.
Please follow the steps to remove the watermark of your mind map.
1. Launch XMind: ZEN,
2. Click Edit > Preferences, (on a Windows PC)
Click XMind: ZEN > Preferences, (on a Mac)
3. Do not circle Display in exported and printed files and click Apply.